In AMA 4 , seven differentiators are presented in table 71, DRE Impairment category Differentiators(AMA 4 P 109), including guarding, loss of reflexes, atrophy etc.The rating was based SOLELY on the injury and NOT improvement(or worsening) with treatment.This was a difficult exercise as patients have usually been treated for a cervical strain by the time they present for Pi assessment!

AMA 5 carried significant changes so that evaluators could now take into account the tretment results.As a result, the DRE rating is based on the objective findings at the eventual time of PI evaluation.THE OBJECTIVE FINDINGS are : muscle spasm, muscle guarding, asymmetric spinal motion(previously called dysmetria), non-verifiable radicular pain, reflexes, neurologic changes such as wasting or loss of sensation, atrophy, radiculopathy etc.imaging studies may assist the evaluator.